Replace project with current server release and Windows setup

Import the 2026-10-09 source release, Fastify/SQLite backend, restored source
assets, and analytics-enabled server build. Replace files from the previous
release while retaining the existing repository history.

Make builds portable across Windows and Linux, configure local startup,
normalize Windows static asset paths, and fix test fixture cleanup and file
URL handling. Exclude local environment settings, databases, dependencies,
validation output, and TypeScript build cache from version control.

Validation: npm ci, static and server builds, 106 arrival tests, and actual
local HTTP checks passed. The full suite passed 467 of 470 tests; three tests
still require QA fixtures omitted from the supplied release, documented in
README-서버실행.md.

scripts/test-arrival-count.mjs

@@ -0,0 +1,48 @@
+import assert from 'node:assert/strict';
+import { access, readFile } from 'node:fs/promises';
+import { test } from 'node:test';
+import { loadTypescript } from './support/load-typescript.mjs';
+
+const moduleURL = new URL('../src/ui/ArrivalCount.ts', import.meta.url);
+assert.equal(await access(moduleURL).then(() => true, () => false), true, 'arrival count presentation module must exist');
+const { renderArrivalCount } = await loadTypescript(moduleURL);
+const element = () => ({ hidden: false, textContent: '', set innerHTML(_value) { assert.fail('numeric copy must use textContent'); } });
+
+test('unknown initial count hides all count nodes without inventing zero', () => {
+  const elements = [element(), element()];
+  renderArrivalCount(elements, undefined);
+  assert.ok(elements.every(node => node.hidden));
+  assert.ok(elements.every(node => node.textContent === ''));
+});
+
+test('server zero is a real visible zero with the exact Korean copy', () => {
+  const elements = [element(), element()];
+  renderArrivalCount(elements, 0);
+  for (const node of elements) { assert.equal(node.hidden, false); assert.equal(node.textContent, '지금까지 0번 도착했어요'); }
+});
+
+test('arrival count groups using Korean locale and updates both placements', () => {
+  const elements = [element(), element()];
+  renderArrivalCount(elements, 1234);
+  for (const node of elements) { assert.equal(node.hidden, false); assert.equal(node.textContent, '지금까지 1,234번 도착했어요'); }
+});
+
+test('failed or invalid reads preserve the last valid count text and visibility', () => {
+  const elements = [element(), element()];
+  renderArrivalCount(elements, 1234);
+  for (const count of [undefined, -1, 0.5, '0', Number.MAX_SAFE_INTEGER + 1, NaN]) {
+    renderArrivalCount(elements, count);
+    for (const node of elements) { assert.equal(node.hidden, false); assert.equal(node.textContent, '지금까지 1,234번 도착했어요'); }
+  }
+});
+
+test('malformed initial count is hidden rather than displayed', () => {
+  for (const count of [-1, 0.5, '0', Number.MAX_SAFE_INTEGER + 1, NaN]) {
+    const node = element(); renderArrivalCount([node], count); assert.equal(node.hidden, true); assert.equal(node.textContent, '');
+  }
+});
+
+test('count presentation has no animation, polling or render-demand dependency', async () => {
+  const source = await readFile(moduleURL, 'utf8');
+  assert.doesNotMatch(source, /innerHTML|requestAnimationFrame|setInterval|setTimeout|RenderDemand|invalidate/);
+});